Air / Vacuum / Stirling Engines
(sometimes known as
operate on the two stroke cycle and rely on an external heat source to
drive the power piston, but not in a conventional manner as they
actually suck the power piston along its stroke.
use heated air (or sometimes steam at very low pressure),
about to ( as
in the picture) with the flywheel rotating, entering a
cylinder until it is full when the cylinder is sealed by a
valve so that the metalwork chills the air (or steam) creating
way sucking the piston to the top of the cylinder with a power stroke.
The flywheel providing the momentum for the next induction of the
The candle engine
listed below is a good example of our vacuum engine plans and complete
versions can be found in our General
Model Steam Engine Kits listing.
shown in the above link, sometimes
known as hot air
on the other hand have a sealed system where one simple type
has a large cylinder where a
very loose fitting displacer piston is encapsulated, sliding up and
cylinder and displacing the trapped air from one side of the piston to
side of this piston the cylinder is heated to warm the air, while the
other side is cooled to chill it.
Because of the displacement of the air from the cold end to the warm
end as the piston travels along its stroke, there is a small amount of
pressure exerted on a much smaller piston (the power piston shown below the crank in this
causing a power stroke. At the other end of the large piston's stroke
the air is chilled, meaning the small piston is now sucked back towards
main pistons chamber, causing a second power stroke.
To make these engines work the pistons need to be offset from each
other at 90 degrees and because of the small change in temperature
between hot and cold, these
engines are not powerful and in the model scales we work with can
really only provide the power needed for fans and the likes.
Our stirling engine pdf plans and diy files show you how to build a
stirling engine at home whether its a new stirling engine diy project, a
desk-top working model
stirling engine or one you've been promising yourself for
out the links on the left for more ready-made options...
|Air Cooled Hot Air Engine
Vacuum Motor -
German Script but
simple design to follow
Fire Eater -
Stirling Engine Blueprint - German
Popular Mechanics Boiler
Plus other engines